(a) Technical Field
The present disclosure relates to a light guide device, and more particularly, to a light guide device which recycles a portion of incident light, to generate backlight, via a retro-reflection principle, to improve the efficiency of backlighting and to improve uniform illumination of an image.
(b) Background Art
Typically, a vehicle headlamp illuminates the area ahead of a vehicle to ensure safe operation of the vehicle during low light conditions, such as at night. A vehicle headlamp emits light having sufficient illuminance to enable the driver to perceive obstacles positioned ahead of the vehicle. Generally, the headlamp includes a lens, a housing, and a bezel. Recently, vehicle headlamps in the related art may further include a light guide device, mounted within the front edge portion of the bezel to generate backlight.
FIG. 1 is an exemplary view that schematically illustrating a conventional light guide device. As shown in FIG. 1, a conventional light guide device includes a light source 1 configured to emit light, a light guide component 2 configured to guide the light emitted from the light source 1, and an optical reflection component 3 disposed at a first surface of the light guide component 2 to reflect the light, incident into the light guide component 2 from the light source 1, to the adjacent surface of the light guide component 2.
In the conventional light guide device, the light emitted from the light source 1 is incident into the light guide component 2 through a first end of the light guide component 2, and is reflected to the adjacent surface of the light guide component 2 by the optical reflection unit 3. The light finally reaches the second end (e.g., the opposite end) of the light guide component 2. The incident light travels into the light guide component 2 through the first end in the longitudinal direction of the light guide component 2 and travels to the second end in the longitudinal direction of the light guide component 2, the light reflected to the adjacent surface of the light guide component 2 provides backlighting. However, the above conventional light guide device reflects a portion of the light incident into the light guide component 2 from the optical reflection component 3 and provides backlighting. However, the remainder of the light passes through the optical reflection component 3 and is not be used for backlighting, and thereby reduces the efficiency of the backlighting.
The above information disclosed in this section is intended merely to aid in the understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.